In the case of Rosemond v. United States (2013), Justus Rosemond was convicted for aiding and abetting a firearm offense during a drug trafficking crime. The Supreme Court had to decide whether, in order to secure a conviction, the government needed to prove that Rosemond intentionally facilitated or encouraged the use of the firearm, or merely that he participated in the drug deal knowing his accomplice would carry a gun. In an opinion delivered by Justice Elena Kagan, it was held that an individual can be found guilty of aiding and abetting a firearms offense if they have foreknowledge that one of their confederates will carry a gun. However, this knowledge must extend beyond mere presence at the scene; there needs to be active participation in some way with respect to carrying out this crime.

In the dissenting opinion for Rosemond v. United States, Justice Alito argued that the majority's interpretation of aiding and abetting law was incorrect. He contended that a person could be convicted as an aider and abettor without having advance knowledge of every detail of the crime. Instead, he suggested it would suffice if they intentionally facilitated some part of it while understanding their role in a broader criminal venture. The justice believed this approach better aligned with historical interpretations and congressional intent behind aiding and abetting statutes. Furthermore, he expressed concern that the majority’s decision might complicate jury instructions by requiring jurors to differentiate between advanced knowledge versus mere awareness or suspicion about certain aspects of a crime.